Suzan Commandeur is the first researcher to succeed in developing in vitro skin cancer models with a heterogeneous group of tumour cells. In vitro models only use living human or animal cells, while in vivo models test drugs directly on living people or animals. Until now researchers used primarily in vitro skin cancer models with cells that were cultured some years previously. This makes the models less realistic because only the strongest cells survive and reproduce and even after only a few weeks they form a homogenous group.

Commandeur figured out how to maintain the heterogeneous composition by directly culturing the removed tumours and integrating them in her models within a few hours. This ensures that the specific characteristics of the cancer cells are maintained during culturing. This method is therefore very suitable for research on how to fight planocellular carcinoma. Approximately 15% of all skin cancer patients suffer from this type of tumour which usually has a heterogeneous composition because it consists of different populations of cancer cells. Researchers often use two-dimensional culture systems which only contain a single cell layer. Commandeur built three-dimensional culture models with more cell layers so that she could make a better study of the interaction between cells. . She did this together with the research group of Dr Abdoel El Ghalbzouri in the research lab of the Department of Dermatology at the LUMC. The lab works closely together with the Leiden Dermatology out-patient department where skin cancers are removed.

The PhD candidate investigated whether her in vitro skin cancer models were also suitable for testing new drugs. Drugs against cancer are always first tested on animals before they reach the market. In such in vivo models, researchers usually use mice that develop skin cancer as a result of exposure to harmful substances or UV radiation. In addition to the ethical objections facing this method there are also limitations: mice skin is very different from human skin. Commandeur made skin cancer models with planocellular carcinoma cells and treated them with the experimental skin cancer drug Erlotinib. The effects of the drug were clearly apparent in the tests. The drug reduced the growth of skin cancer cells in the skin model and clear side-effects could be observed, such as a strong flaking of the stratum corneum.

Commandeur is of the opinion that these new models can bring about substantial changes to the test phase for skin cancer drugs. As no live animals are required, the test phase can be cheaper and shorter. This does not mean that animal testing can be entirely abandoned, but in the long run this kind of testing would only be required at a later stage than now. Drug manufacturers are interested in these new skin cancer models and Commandeur has been working since July 2012 at the Leiden company Aeon Astron Europe B.V. to bring the models to market through a spin-off company.